This Integer32 (0..14), in dB, sets the attenuation applied at the transmit side of this DS0 channel, relative to a 0 dB baseline. This is the transmit counterpart to ds0InputGain, letting an admin correct for a network loss plan where a channel's outgoing audio is too loud relative to other circuits, and changes take effect immediately even during an active call. For instance, an admin fielding complaints that a specific trunk's callers sound too loud compared to others could increase ds0OutputAttenuation on that DS0 to bring it in line.